我々は感謝して分子デバイスの研究に使用される試薬の彼らの寛大な寄付のための分析技術/アルクトゥルスを認めます。我々はまた、死後、人間の脳組織を提供するためにハーバード大学の組織のリソースセンターに感謝資金 ：。RO1MH76060とP50MH080272。

<ol>
	<li>Imbeaud, S., Graudens, E., Boulanger, V., Barlet, X., Zaborski, P., Eveno, E., Mueleer, O., Schroeder, A., Auffray, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Towards+standardization+of+RNA+quality+assessment+using+user-independent+classifiers+of+microcapillary+electrophoresis+traces.">Towards standardization of RNA quality assessment using user-independent classifiers of microcapillary electrophoresis traces.</a> Nucleic Acids Res. 33, e56-e56 (2005).</li></ol>

このビデオ記事の生産は、Life Technologies社が後援した。

ここで、我々は、アルクトゥルスXTシステムと関連するRNA抽出キットを使用して異種の死後の脳組織から均質な細胞集団を抽出するためのプロトコルをカスタマイズしよう。上述のように、我々は、RNAの完全性を最大化するために、同社が提供するオリジナルプロトコルにいくつかの変更を行っている。単一細胞の正常なキャプチャリングは、単に良いRNAとの最大のセルを実現するために、キャプチャする前に手順を最適化に依存する。これらの手順は、組織の切片や染色に関連するさまざまなパラメータが含まれています。一言で言えば、組織の準備に関して、これらが含まれます：1）、2の切削時に温度勾配を減少）のみ4、氷の上のすべての脱水の手順を実行して、スライドごとに2セクション、3）を配置すること）の増加）染色、5のRNase阻害剤を追加する3分に最後の100％エタノールで脱水期間。 キャプチャに関しては、我々はポイカプセルHSキャップの組み合わせと感じ、マクロの設定上のソフトウェアで、最適な結果を確認する必要があります。高湿度が大幅に組織&quot;リフト&quot;を減少させるように湿度制御環境は、単一細胞を捕捉するために重要です。高温はまた、RNAの品質に悪影響を与えることができる。 PicoPureキットでRNA分離プロトコール中に、2つの洗浄ステップがあります。すべての洗浄バッファーが最終的なサンプル中のバッファのいずれかが存在するが、増幅のための小さい開始RNAにつながるとして、RNA溶出のための別のマイクロ遠心チューブに移す前に削除されていることを確認することが重要です。これを確実にするために、我々は、提供するプロトコルで提案されている2.5分の代わりに2分間の最後の洗浄ステップを遠心してください。 ほとんどの部分については、リニア増幅プロトコールは、製造元の指示に従ってでした。このプロトコルを使用するただし、次の2つの重要な点を考慮する必要があります：1）サーマルサイクラーで0.5ミリリットルのブロックと組み合わせて提供される唯一の0.5ミリリットルチューブを使用することにより、チューブ間のサンプルの過剰移籍を経由してRNAの損失を制限しようとする、および2）cDNAの精製のための精製カラムにサンプルを転送するとき、最初の転送の後にサンプルチューブをスピンダウンしてください。これは、精製カラムに追加するため、cDNAの回収を増加させることができるサンプルの追加1 - 2ulになります。 あなたの限られたaRNAのサンプルのビオチン標識用ターボ末端標識キットを利用する場合、我々は余分な数μlを添加すると収率は、列から抽出された標識RNAを高めるために、遠心分離のステップの前に水から出ているとのこと。遠心分離の余分な分はあなたがそのようなFFPE組織などの劣化した組織、と作業している場合は特に、この点で役立ちます。 我々は、このプロトコルは、異種の死後の脳組織内で、ユーザーがそのような単一の細胞集団としての小さな均質構造を、単離するために有効になると確信しています。これは、調査中の特定の細胞タイプをターゲットに結果につながる、脳内の様々な層に位置し、周囲の構造および他の細胞タイプの希釈効果を、減らすことができます。得られたRNAの質は、マイクロアレイ研究には十分なので、我々は、病気の状態に影響を受ける特定の細胞集団の特定の分子の署名を特定するために始めることができます。

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>4.5&#x201D; Forceps</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>82027-392</td>
<td>&nbsp;</td>
<tr>
<td>Arcturus XT&trade; Laser-Capture Microdissection (LCM) System</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>13821-00</td>
<td>&nbsp;</td>
<tr>
<td>CapSure&trade; HS LCM Caps</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>LCM 0214</td>
<td>&nbsp;</td>
<tr>
<td>CapSure&reg; Macro LCM Caps</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>LCM 0211</td>
<td>&nbsp;</td>
<tr>
<td>Experion&trade; Automated Electrophoresis Station</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7001</td>
<td>&nbsp;</td>
<tr>
<td>Experion&trade; RNA HighSens Chips</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7155</td>
<td>10 chips</td>
</tr>
<tr>
<td>Experion&#x2122; RNA HighSens Reagents</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7156</td>
<td>10 chips</td>
</tr>
<tr>
<td>Experion&#x2122; RNA StdSens Chips</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7153</td>
<td>10 chips</td>
</tr>
<tr>
<td>Experion&trade; RNA StdSens Reagents</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7154</td>
<td>10 chips</td>
</tr>
<tr>
<td>Falcon&reg; polypropylene Conical tube</td>
<td>&nbsp;</td>
<td>Becton-Dickinson Labware</td>
<td>352070</td>
<td>&nbsp;</td>
<tr>
<td>GeneAmp&reg; thin-walled reaction tube with domed cap</td>
<td>&nbsp;</td>
<td>Applied Biosystems</td>
<td>N8010611</td>
<td>&nbsp;</td>
<tr>
<td>GeneChip&reg; Human X3P array</td>
<td>&nbsp;</td>
<td>Affymetrix</td>
<td>900516</td>
<td>6 chips</td>
</tr>
<tr>
<td>Histogene&reg; LCM Frozen Section Staining kit</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>KIT0401</td>
<td>For staining solution, jars, ethanols and Xylene</td>
</tr>
<tr>
<td>Histogene&trade; LCM slides</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>12231-00</td>
<td>&nbsp;</td>
<tr>
<td>Micro Slide Box</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>48444-004</td>
<td>&nbsp;</td>
<tr>
<td>Microm HM 505E cryostat</td>
<td>&nbsp;</td>
<td>Thermo Scientific</td>
<td>22-050-350</td>
<td>Catalogue number for similar product as current product no longer available</td>
</tr>
<tr>
<td>Microprocessor Controlled 280 series Water bath</td>
<td>&nbsp;</td>
<td>Thermo Electron Corporation</td>
<td>51221048</td>
<td>Model 282</td>
</tr>
<tr>
<td>Molecular Sieve</td>
<td>&nbsp;</td>
<td>EMD&trade;</td>
<td>MX1583L-1</td>
<td>&nbsp;</td>
<tr>
<td>NanoDrop 1000 Spectrophotometer</td>
<td>&nbsp;</td>
<td>Thermo Scientific</td>
<td>n/a</td>
<td>The NanoDrop 1000 is not available anymore, but the NanoDrop 2000 is comparable.</td>
</tr>
<tr>
<td>Nuclease-free water</td>
<td>&nbsp;</td>
<td>Ambion&reg;</td>
<td>AM9932</td>
<td>&nbsp;</td>
<tr>
<td>PEN Membrane glass slides</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>LCM 0522</td>
<td>&nbsp;</td>
<tr>
<td>PicoPure&reg; RNA Isolation kit</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>KIT0204</td>
<td>&nbsp;</td>
<tr>
<td>RiboAmp&reg;HSPLUS with Biotin labeling</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>KIT0511B</td>
<td>12 reactions Includes TURBO biotin labeling&trade; kit</td>
</tr>
<tr>
<td>RNase Zap&reg;</td>
<td>&nbsp;</td>
<td>Ambion&reg;</td>
<td>AM9780/2</td>
<td>&nbsp;</td>
<tr>
<td>RNase-Free DNase Set</td>
<td>&nbsp;</td>
<td>Qiagen</td>
<td>79254</td>
<td>&nbsp;</td>
<tr>
<td>RNasin&reg; Plus</td>
<td>&nbsp;</td>
<td>Promega</td>
<td>N261B</td>
<td>&nbsp;</td>
<tr>
<td>SuperScript&trade; III Reverse Transcriptase</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>18080-044</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

obtaining high quality rna from single cell populations in human postmortem brain tissue

我々は、レイヤーIIIの錐体細胞の遺伝子発現プロファイルを問い合わせることにより、統合失調症の患者に見られる上側頭回の灰白質の減少を調査することを提案した。それは、大脳皮質は多様な領域、層および別個の細胞および分子組成物およびそのための差動遺伝子発現プロファイルによって特徴づけられるそれぞれの細胞タイプを、構成する非常に不均質構造であることはよく知られています。組織の不均一性の交絡の影響を回避するために、我々は特定の細胞型、すなわち錐体細胞を単離するために、レーザーキャプチャーマイクロダイセクション（LCM）を使用。 Histogene染色液で染色された約500個の錐体細胞は、アルクトゥルスXT LCMシステムを使用して捕獲された。 RNAを捕捉細胞から単離され、アルクトゥルス/分子デバイスのキットを用いてT7ベースの線形増幅を2回施行した。 Experion LabChip（Bio - Rad社）ゲルや電気泳動図では、マイクロアレイに必要な過去の600ntを拡張する転写産物の長さで、良質の（m）のRNAを示した。得られたmRNAの量は2.5、A260/280比で示されるように許容可能な平均値サンプルの純度で、51μgの平均値。遺伝子発現は、アフィメトリクスからヒューマンX3PのGeneChipプローブアレイを用いてプロファイリングした。

Watch this Scientific Journal Video about Obtaining High Quality RNA from Single Cell Populations in Human Postmortem Brain Tissue at JoVE.com

Obtaining High Quality RNA from Single Cell Populations in Human Postmortem Brain Tissue

我々は、死後、人間の脳の上側頭回の層IIIの均質な細胞集団、錐体細胞からRNAを分離して抽出するためにレーザーキャプチャーマイクロダイセクションを使用してプロセスを説明します。私たちは、その後直線的に（T7ベース）mRNAを増幅し、Affymetrix社人間X3Pマイクロアレイにサンプルをハイブリダイズする。

人間の死後の脳組織における単一細胞から、高品質のRNAを取得

We proposed to investigate the gray matter reduction in the superior temporal gyrus seen in schizophrenia patients, by interrogating gene expression ...

obtaining-high-quality-rna-from-single-cell-populations-human

Research

JoVE Journal

Biology

30.5K ビュー.  McLean Hospital. 我々は、死後、人間の脳の上側頭回の層IIIの均質な細胞集団、錐体細胞からRNAを分離して抽出するためにレーザーキャプチャーマイクロダイセクションを使用してプロセスを説明します。私たちは、その後直線的に（T7ベース）mRNAを増幅し、Affymetrix社人間X3Pマイクロアレイにサンプルをハイブリダイズする。

ビデオ: Obtaining High Quality RNA from Single Cell Populations in Human Postmortem Brain Tissue

Obtaining Eggs from Xenopus laevis Females

The eggs of Xenopus laevis intact, lysed, and/or fractionated are useful for a wide variety of experiments. This protocol shows how to induce egg laying, collect and dejelly the eggs, and sort the eggs to remove any damaged eggs.

The eggs of Xenopus laevis intact, lysed, and/or fractionated are useful for a wide variety of experiments. This protocol shows how to induce egg laying, collect and dejelly the eggs, and sort the eggs to remove any damaged eggs.

アフリカツメガエル女性から卵子を入手

The eggs of Xenopus laevis intact, lysed, and/or fractionated are useful for a wide variety of experiments. This protocol shows how to induce egg laying, ...

生物学

Neuronal Nuclei Isolation from Human Postmortem Brain Tissue

Neurons in the human brain become postmitotic largely during prenatal development, and thus maintain their nuclei throughout the full lifespan. However, little is known about changes in neuronal chromatin and nuclear organization during the course of development and aging, or in chronic neuropsychiatric disease. However, to date most chromatin and DNA based assays (other than FISH) lack single cell resolution. To this end, the considerable cellular heterogeneity of brain tissue poses a significant limitation, because typically various subpopulations of neurons are intermingled with different types of glia and other non-neuronal cells. One possible solution would be to grow cell-type specific cultures, but most CNS cells, including neurons, are ex vivo sustainable, at best, for only a few weeks and thus would provide an incomplete model for epigenetic mechanisms potentially operating across the full lifespan.  Here, we provide a protocol to extract and purify nuclei from frozen (never fixed) human postmortem brain. The method involves extraction of nuclei in hypotonic lysis buffer, followed by ultracentrifugation and immunotagging with anti-NeuN antibody. Labeled neuronal nuclei are then collected separately using fluorescence-activated sorting. This method should be applicable to any brain region in a wide range of species and suitable for chromatin immunoprecipitation studies with site- and modification-specific anti-histone antibodies, and for DNA methylation and other assays. 

The cellular heterogeneity of brain tissue poses a significant limitation for the study of epigenetic markings in chromatin because most assays lack single cell resolution. Neurons typically are intermingled with glia and other non-neuronal cells. We provide a protocol to extract and collect neuronal nuclei from human brain.

人間の死後の脳組織から神経細胞核の単離

Neurons in the human brain become postmitotic largely during prenatal development, and thus maintain their nuclei throughout the full lifespan. However, ...

Generation of Single-Cell Suspensions from Mouse Neural Tissue

Within the nervous system, hundreds of neuronal and glial cell types have been described. Each specific cell type in the brain or spinal cord has a repertoire of cell surface molecules, or molecular determinants, through which it can be identified and characterized. Currently, robust cell identification and separation technologies require single-cell preparations to be generated while simultaneously limiting cell death and destruction of characteristic surface protein. The gentleMACS Dissociator, when used in combination with trypsin or papain-based dissociation kits, can effectively and gently dissociate brain tissue while preserving antigen epitopes and limiting cell loss. Standardized preparation of single-cell suspensions is achieved using C Tubes and optimized, preset gentleMACS Programs. Once generated, single-cell suspensions can be treated with monoclonal conjugates like Anti-Prominin-1 MicroBeads, which identify neural progenitors, or purified further using Myelin Removal Beads.

Dissociating cells from specific tissue types requires specific parameters for tissue aggitation to obtain a high volume of viable, culturable cells. The Miltenyi gentleMACS Dissociator optimizes this task with a simple, practical protocol. In this publication the use of this apparatus on nerual tissue is explained.

マウス神経組織から単細胞懸濁液の生成

Within the nervous system, hundreds of neuronal and glial cell types have been described. Each specific cell type in the brain or spinal cord has a ...

Single-cell Suction Recordings from Mouse Cone Photoreceptors

Rod and cone photoreceptors in the retina are responsible for light detection. In darkness, cyclic nucleotide-gated (CNG) channels in the outer segment are open and allow cations to flow steadily inwards across the membrane, depolarizing the cell. Light exposure triggers the closure of the CNG channels, blocks the inward cation current flow, and thus results in cell hyperpolarization. Based on the polarity of photoreceptors, a suction recording method was developed in 1970s that, unlike the classic patch-clamp technique, does not require penetrating the plasma membrane 1. Drawing the outer segment into a tightly-fitting glass pipette filled with extracellular solution allows recording the current changes in individual cells upon test-flash exposure. However, this well-established "outer-segment-in (OS-in)" suction recording is not suitable for mouse cone recordings, because of the low percentage of cones in the mouse retina (3%) and the difficulties in identifying the cone outer segments. Recently, an inner-segment-in (IS-in) recording configuration was developed to draw the inner segment/nuclear region of the photoreceptor into the recording pipette 2,3. In this video, we will show how to record from individual mouse cone photoresponses using single-cell suction electrode.

We will show how to record flash responses from single mouse cones using a suction electrode.

マウスの錐体光受容体からの単一細胞サクション録音

Rod and cone photoreceptors in the retina are responsible for light detection. In darkness, cyclic nucleotide-gated (CNG) channels in the outer segment ...

Robust Generation of Hepatocyte-like Cells from Human Embryonic Stem Cell Populations

Despite progress in modelling human drug toxicity, many compounds fail during clinical trials due to unpredicted side effects. The cost of clinical studies are substantial, therefore it is essential that more predictive toxicology screens are developed and deployed early on in drug development (Greenhough et al 2010). Human hepatocytes represent the current gold standard model for evaluating drug toxicity, but are a limited resource that exhibit variable function. Therefore, the use of immortalised cell lines and animal tissue models are routinely employed due to their abundance. While both sources are informative, they are limited by poor function, species variability and/or instability in culture (Dalgetty et al 2009). Pluripotent stem cells (PSCs) are an attractive alternative source of human hepatocyte like cells (HLCs) (Medine et al 2010). PSCs are capable of self renewal and differentiation to all somatic cell types found in the adult and thereby represent a potentially inexhaustible source of differentiated cells. We have developed a procedure that is simple, highly efficient, amenable to automation and yields functional human HLCs (Hay et al 2008 ; Fletcher et al 2008 ; Hannoun et al 2010 ; Payne et al 2011 and Hay et al 2011). We believe our technology will lead to the scalable production of HLCs for drug discovery, disease modeling, the construction of extra-corporeal devices and possibly cell based transplantation therapies.

This article will focus on the generation of human hepatic endoderm from human embryonic stem cell populations.

ヒト胚性幹細胞集団から肝細胞様細胞の堅牢な生成

Despite progress in modelling human drug toxicity, many compounds fail during clinical trials due to unpredicted side effects. The cost of clinical ...

Generation of High Quality Chromatin Immunoprecipitation DNA Template for High-throughput Sequencing (ChIP-seq)

ChIP-sequencing (ChIP-seq) methods directly offer whole-genome coverage, where combining chromatin immunoprecipitation (ChIP) and massively parallel sequencing can be utilized to identify the repertoire of mammalian DNA sequences bound by transcription factors in vivo. "Next-generation" genome sequencing technologies provide 1-2 orders of magnitude increase in the amount of sequence that can be cost-effectively generated over older technologies thus allowing for ChIP-seq methods to directly provide whole-genome coverage for effective profiling of mammalian protein-DNA interactions.
For successful ChIP-seq approaches, one must generate high quality ChIP DNA template to obtain the best sequencing outcomes. The description is based around experience with the protein product of the gene most strongly implicated in the pathogenesis of type 2 diabetes, namely the transcription factor transcription factor 7-like 2 (TCF7L2). This factor has also been implicated in various cancers.
Outlined is how to generate high quality ChIP DNA template derived from the colorectal carcinoma cell line, HCT116, in order to build a high-resolution map through sequencing to determine the genes bound by TCF7L2, giving further insight in to its key role in the pathogenesis of complex traits.

Generation of High Quality Chromatin Immunoprecipitation DNA Template for High-throughput Sequencing ChIP-seq

The combination of chromatin immunoprecipitation and ultra-high-throughput sequencing (ChIP-seq) can identify and map protein-DNA interactions in a given tissue or cell line. Outlined is how to generate a high quality ChIP template for subsequent sequencing, using experience with the transcription factor TCF7L2 as an example.

ハイスループットシーケンシングのための高品質クロマチン免疫沈降DNAテンプレート（チップ-SEQ）の生成

ChIP-sequencing (ChIP-seq) methods directly  offer whole-genome coverage, where combining chromatin immunoprecipitation  (ChIP) and massively parallel ...

A Laser Capture Microdissection Protocol That Yields High Quality RNA from Fresh-frozen Mouse Bones

RNA yield and integrity are decisive for RNA analysis. However, it is often technically challenging to maintain RNA integrity throughout the entire laser capture microdissection (LCM) procedure. Since LCM studies work with low amounts of material, concerns about limited RNA yields are also important. Therefore, an LCM protocol was developed to obtain sufficient quantity of high-quality RNA for gene expression analysis in bone cells. The effect of staining protocol, thickness of cryosections, microdissected tissue quantity, RNA extraction kit, and LCM system used on RNA yield and integrity obtained from microdissected bone cells was evaluated. Eight-&#181;m-thick frozen bone sections were made using an adhesive film and stained using a rapid protocol for a commercial LCM stain. The sample was sandwiched between a polyethylene terephthalate (PET) membrane and the adhesive film. An LCM system that uses gravity for sample collection and a column-based RNA extraction method were used to obtain high quality RNAs of sufficient yield. The current study focusses on mouse femur sections. However, the LCM protocol reported here can be used to study in situ gene expression in cells of any hard tissue in both physiological conditions and disease processes.

A laser capture microdissection (LCM) protocol was developed to obtain sufficient quantity of high-quality RNA for gene expression analysis in bone cells. The current study focusses on mouse femur sections. However, the LCM protocol reported here can be used to study gene expression in cells of any hard tissue.

新鮮な凍結マウスの骨から高品質のRNAを得るレーザー捕捉微解剖プロトコル

RNA yield and integrity are decisive for RNA analysis. However, it is often technically challenging to maintain RNA integrity throughout the entire laser ...

Quantitative Proteomics Workflow using Multiple Reaction Monitoring Based Detection of Proteins from Human Brain Tissue

The proteomic analysis of the human brain tissue over the last decade has greatly enhanced our understanding of the brain. However, brain related disorders continue to be a major contributor of deaths around the world, necessitating the need for even greater understanding of their pathobiology. Traditional antibody-based techniques like western blotting or immunohistochemistry suffer from being low-throughput besides being labor-intensive and qualitative or semi-quantitative. Even conventional mass spectrometry-based shotgun approaches fail to provide conclusive evidence to support a certain hypothesis. Targeted proteomics approaches are largely hypothesis driven and differ from the conventional shotgun proteomics approaches that have been long in use. Multiple reaction monitoring is one such targeted approach that requires the use of a special mass spectrometer called the tandem quadrupole mass spectrometer or triple quadrupole mass spectrometer. In the current study, we have systematically highlighted the major steps involved in performing a successful tandem quadrupole mass spectrometry-based proteomics workflow using human brain tissue with an aim to introduce this workflow to a broader research community.

The protocol aims to introduce the use of a triple quadrupole mass spectrometer for Multiple Reaction Monitoring (MRM) of proteins from clinical samples. We have provided a systematic workflow starting from sample preparation to data analysis for clinical samples with all the necessary precautions to be taken.

ヒト脳組織からのタンパク質の多発反応モニタリングを用いた定量的プロテオミクスワークフロー

The proteomic analysis of the human brain tissue over the last decade has greatly enhanced our understanding of the brain. However, brain related ...

Tissue Collection and RNA Extraction from the Human Osteoarthritic Knee Joint

Osteoarthritis (OA) is a chronic and degenerative joint disease most often affecting the knee. As there is currently no cure, total knee arthroplasty (TKA) is a common surgical intervention. Experiments using primary human OA tissues obtained from TKA provide the capability to investigate disease mechanisms ex vivo. While OA was previously thought to impact mainly the cartilage, it is now known to impact multiple tissues in the joint. This protocol describes patient selection, sample processing, tissue homogenization, RNA extraction, and quality control (based on RNA purity, integrity, and yield) from each of seven unique tissues to support disease mechanism investigation in the knee joint. With informed consent, samples were obtained from patients undergoing TKA for OA. Tissues were dissected, washed, and stored within 4 h of surgery by flash freezing for RNA or formalin fixation for histology. Collected tissues included articular cartilage, subchondral bone, meniscus, infrapatellar fat pad, anterior cruciate ligament, synovium, and vastus medialis oblique muscle. RNA extraction protocols were tested for each tissue type. The most significant modification involved the method of disintegration used for low-cell, high-matrix, hard tissues (considered as cartilage, bone, and meniscus) versus relatively high-cell, low-matrix, soft tissues (considered as fat pad, ligament, synovium, and muscle). It was found that pulverization was appropriate for hard tissues, and homogenization was appropriate for soft tissues. A proclivity for some subjects to yield higher RNA integrity number (RIN) values than other subjects consistently across multiple tissues was observed, suggesting that underlying factors such as disease severity may impact RNA quality. The ability to isolate high-quality RNA from primary human OA tissues provides a physiologically relevant model for sophisticated gene expression experiments, including sequencing, that can lead to clinical insights that are more readily translated to patients.

Primary tissues obtained from patients following total knee arthroplasty provide an experimental model for osteoarthritis research with maximal clinical translatability. This protocol describes how to identify, process, and isolate RNA from seven unique knee tissues to support mechanistic investigation in human osteoarthritis.

ヒト変形性膝関節からの組織採取とRNA抽出

Osteoarthritis (OA) is a chronic and degenerative joint disease most often affecting the knee. As there is currently no cure, total knee arthroplasty ...

Nuclei Isolation from Adult Mouse Kidney for Single-Nucleus RNA-Sequencing

The kidneys regulate diverse biological processes such as water, electrolyte, and acid-base homeostasis. Physiological functions of the kidney are executed by multiple cell types arranged in a complex architecture across the corticomedullary axis of the organ. Recent advances in single-cell transcriptomics have accelerated the understanding of cell type-specific gene expression in renal physiology and disease. However, enzyme-based tissue dissociation protocols, which are frequently utilized for single-cell RNA-sequencing (scRNA-seq), require mostly fresh (non-archived) tissue, introduce transcriptional stress responses, and favor the selection of abundant cell types of the kidney cortex resulting in an underrepresentation of cells of the medulla.
Here, we present a protocol that avoids these problems. The protocol is based on nuclei isolation at 4 &#176;C from frozen kidney tissue. Nuclei are isolated from a central piece of the mouse kidney comprised of the cortex, outer medulla, and inner medulla. This reduces the overrepresentation of cortical cells typical for whole-kidney samples for the benefit of medullary cells such that data will represent the entire corticomedullary axis at sufficient abundance. The protocol is simple, rapid, and adaptable and provides a step towards the standardization of single-nuclei transcriptomics in kidney research.

Here, we present a protocol to isolate high-quality nuclei from frozen mouse kidneys that improve the representation of medullary kidney cell types and avoids the gene expression artifacts from enzymatic tissue dissociation.